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        <h2>
          <span class="refentrytitle">randh</span>
        </h2>
        <p>randh — 
      Generates random numbers and holds them for a period of time.
          </p>
      </div>
      <div class="refsect1">
        <a id="idp140830528"></a>
        <h2>Description</h2>
        <p>
      Generates random numbers and holds them for a period of time.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp140901200"></a>
        <h2>Syntax</h2>
        <pre class="synopsis">ares <span class="command"><strong>randh</strong></span> xamp, xcps [, iseed] [, isize] [, ioffset]</pre>
        <pre class="synopsis">kres <span class="command"><strong>randh</strong></span> kamp, kcps [, iseed] [, isize] [, ioffset]</pre>
      </div>
      <div class="refsect1">
        <a id="idp140904912"></a>
        <h2>Initialization</h2>
        <p>
      <span class="emphasis"><em>iseed</em></span> (optional, default=0.5) -- seed value for the recursive pseudo-random formula. A value between 0 and +1 will produce an initial output of <span class="emphasis"><em>kamp * iseed.</em></span> A negative value will cause seed re-initialization to be skipped. A value greater than 1 will seed from system time, this is the best option to generate a different random sequence for each run.
    </p>
        <p>
      <span class="emphasis"><em>isize</em></span> (optional, default=0) -- if zero, a 16 bit number is generated. If non-zero, a 31-bit random number is generated. Default is 0.
    </p>
        <p>
      <span class="emphasis"><em>ioffset</em></span> (optional, default=0) -- a base value added to the random result. New in Csound version 4.03.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp140909696"></a>
        <h2>Performance</h2>
        <p>
      <span class="emphasis"><em>kamp, xamp</em></span> -- range over which random numbers are distributed.
    </p>
        <p>
      <span class="emphasis"><em>kcps, xcps</em></span> -- the frequency which new random numbers are generated.
    </p>
        <p>
      The internal pseudo-random formula produces values which are uniformly distributed over the range -<span class="emphasis"><em>kamp</em></span> to +<span class="emphasis"><em>kamp</em></span>. <span class="emphasis"><em>rand</em></span> will thus generate uniform white noise with an R.M.S value of <span class="emphasis"><em>kamp / root 2</em></span>.
    </p>
        <p>
      The remaining units produce band-limited noise: the <span class="emphasis"><em>kcps</em></span> and <span class="emphasis"><em>xcps</em></span> parameters permit the user to specify that new random numbers are to be generated at a rate less than the sampling or control frequencies. <span class="emphasis"><em>randh</em></span> will hold each new number for the period of the specified cycle.
    </p>
      </div>
      <div class="refsect1">
        <a id="idp140916800"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the randh opcode. It uses the file <a class="ulink" href="examples/randh.csd" target="_top"><em class="citetitle">randh.csd</em></a>.
      </p>
        <div class="example">
          <a id="idp140918656"></a>
          <p class="title">
            <strong>Example 733. Example of the randh opcode.</strong>
          </p>
          <div class="example-contents">
            <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
<span class="comment">; Select audio/midi flags here according to platform</span>
-odac     <span class="comment">;;;realtime audio out</span>
<span class="comment">;-iadc    ;;;uncomment -iadc if RT audio input is needed too</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o randh.wav -W ;;; for file output any platform</span>
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">ksmps</span> <span class="op">=</span> 32
<span class="ohdr">nchnls</span> <span class="op">=</span> 2
<span class="ohdr">0dbfs</span>  <span class="op">=</span> 1

<span class="oblock">instr</span> 1	<span class="comment">;same values every time</span>

krnd <span class="opc">randh</span> 100, 10
     <span class="opc">printk2</span> krnd			<span class="comment">; look </span>
aout <span class="opc">oscili</span> 0.8, 440<span class="op">+</span>krnd, 1		<span class="comment">; &amp; listen</span>
     <span class="opc">outs</span> aout, aout

<span class="oblock">endin</span>

<span class="oblock">instr</span> 2	<span class="comment">;different values every time</span>

krnd <span class="opc">randh</span> 100, 10, 10			<span class="comment">; seed from system clock</span>
     <span class="opc">printk2</span> krnd			<span class="comment">; look </span>
aout <span class="opc">oscili</span> 0.8, 440<span class="op">+</span>krnd, 1		<span class="comment">; &amp; listen</span>
     <span class="opc">outs</span> aout, aout

<span class="oblock">endin</span>
<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>
<span class="stamnt">f</span> 1 0 16384 10 1	<span class="comment">;sine wave.</span>

<span class="stamnt">i</span> 1 0 1
<span class="stamnt">i</span> 2 2 1
<span class="stamnt">e</span>
<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
          </div>
        </div>
        <p><br class="example-break" />
     </p>
        <p>
      The example will produce the following output:
      </p>
        <pre class="screen">
 i1    50.00000
 i1    50.00305
 i1    97.68677
 i1   -44.25354
 i1   -61.56006
 i1   -75.91248
 i1    67.57202
 i1    12.83875
 i1     5.39551
 i1   -95.18738

WARNING: Seeding from current time 684387922

 i2   -13.81226
 i2   -16.49475
 i2    69.51904
 i2    35.04944
 i2    47.47925
 i2    63.25378
 i2   -59.61914
 i2    50.93079
 i2    -6.46362
 i2     5.89294
      </pre>
        <p>
    </p>
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      <div class="refsect1">
        <a id="idp140924864"></a>
        <h2>See Also</h2>
        <p>
      <a class="link" href="rand.html" title="rand"><em class="citetitle">rand</em></a>,
      <a class="link" href="randi.html" title="randi"><em class="citetitle">randi</em></a>
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